compose/foundation/foundation/integration-tests/foundation-demos/src/main/java/androidx/compose/foundation/demos/text/ComposeTextPointerIcon.kt

/*
 * Copyright 2024 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package androidx.compose.foundation.demos.text

import androidx.compose.foundation.ExperimentalFoundationApi
import androidx.compose.foundation.border
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.rememberScrollState
import androidx.compose.foundation.text.BasicTextField
import androidx.compose.foundation.text.input.rememberTextFieldState
import androidx.compose.foundation.text.selection.SelectionContainer
import androidx.compose.foundation.verticalScroll
import androidx.compose.material.Text
import androidx.compose.material.TextField
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.setValue
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.input.pointer.PointerIcon
import androidx.compose.ui.input.pointer.pointerHoverIcon
import androidx.compose.ui.text.SpanStyle
import androidx.compose.ui.text.buildAnnotatedString
import androidx.compose.ui.text.font.FontWeight
import androidx.compose.ui.text.withStyle
import androidx.compose.ui.tooling.preview.Preview
import androidx.compose.ui.unit.dp

private enum class ParentOverride { None, Override, NoOverride }

@Preview
@Composable
fun TextPointerIconDemo() {
    Column(
        modifier = Modifier
            .padding(horizontal = 32.dp)
            .verticalScroll(rememberScrollState()),
        verticalArrangement = Arrangement.spacedBy(16.dp),
    ) {
        Text(
            """The texts below demonstrate how different pointer hover icons work on
                | different texts and text fields with different permutations of
                | overrideDescendants."""
                .trimMargin().replace("\n", "")
        )
        IconDemoRectangle(parentOverride = ParentOverride.None, textOverride = false)
        IconDemoRectangle(parentOverride = ParentOverride.None, textOverride = true)
        IconDemoRectangle(parentOverride = ParentOverride.NoOverride, textOverride = false)
        IconDemoRectangle(parentOverride = ParentOverride.NoOverride, textOverride = true)
        IconDemoRectangle(parentOverride = ParentOverride.Override, textOverride = false)
        IconDemoRectangle(parentOverride = ParentOverride.Override, textOverride = true)
    }
}

@Composable
private fun IconDemoRectangle(parentOverride: ParentOverride, textOverride: Boolean) {
    val rectanglePointerIconModifier = when (parentOverride) {
        ParentOverride.None -> Modifier
        else -> Modifier.pointerHoverIcon(
            icon = PointerIcon.Hand,
            overrideDescendants = parentOverride == ParentOverride.Override
        )
    }

    Column(
        modifier = Modifier
            .then(rectanglePointerIconModifier)
            .border(1.dp, Color.LightGray)
            .padding(16.dp),
        verticalArrangement = Arrangement.spacedBy(16.dp)
    ) {
        val annotatedString = buildAnnotatedString {
            when (parentOverride) {
                ParentOverride.None -> {
                    append("This box does ")
                    withStyle(SpanStyle(fontWeight = FontWeight.Bold)) { append("not") }
                    append(" set a pointer hover icon.")
                }

                else -> {
                    append("This box sets the hand pointer icon with ")
                    appendCode("overrideDescendants = ${parentOverride == ParentOverride.Override}")
                    append(".")
                }
            }
            append(" Each Text/TextField uses ")
            appendCode("overrideDescendants = $textOverride")
            append(" when setting their pointer hover icons.")
        }
        Text(annotatedString)
        IconDemoColumn(overrideDescendants = textOverride)
    }
}

@OptIn(ExperimentalFoundationApi::class)
@Composable
private fun IconDemoColumn(overrideDescendants: Boolean) {
    val borderMod = Modifier.border(1.dp, Color.LightGray)
    val iconMod = borderMod.pointerHoverIcon(PointerIcon.Crosshair, overrideDescendants)
    Column(verticalArrangement = Arrangement.spacedBy(16.dp)) {
        Text("Regular Text, icon not set", borderMod)

        Text("Regular Text, icon crosshair", iconMod)

        SelectionContainer {
            Text("Selectable Text, icon not set", borderMod)
        }

        SelectionContainer {
            Text("Selectable Text, icon crosshair", iconMod)
        }

        var nonMod by remember { mutableStateOf("TextField, icon not set") }
        TextField(nonMod, { nonMod = it }, borderMod)

        var mod by remember { mutableStateOf("TextField, icon crosshair") }
        TextField(mod, { mod = it }, iconMod)

        val nonModTfs = rememberTextFieldState("BTF2, icon not set")
        BasicTextField(nonModTfs, borderMod)

        val modTfs = rememberTextFieldState("BTF2, icon crosshair")
        BasicTextField(modTfs, iconMod)
    }
}